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HORSFORD & NICHOLS.

Safety. Lamp.

Patented Oct. 30, 1855.

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UNITED STATES PATNT QFTQF.

E. N. HORSFORD, OF CAMBRIDGE, AND J. R. NICHOLS, OF HAVERHILL,MASSACHUSETTS.

LAMP FOR BURNING VOLATILE LIQUIDS.

Specification of Letters Patent No. 13,729, dated October 30, 1855.

To all whom it may concern:

Be it known that we, E. N. HORSFORD, of Cambridge, Middlesex county, andJAMES R. NIoHoLs, of Haverhill, in thecounty of Essex, State ofMassachusetts, have invented a certain new and useful Safety-Lamp, andthat the following is a full, clear, and exact description of theprinciple or character which distinguishes it from all other thingsbefore known and of the usual manner of making, modifying, and using thesame.

Our invention consists in certain improvements in safety lamps, for thepurpose of more effectually guarding against the frequent and seriousaccident in the use of lamps for burning volatile and highly combustibleliquids.

The main features of improvement are as follows: First, in preventingthe contents of the lamp from running out when the lamp may beoverturned; second, in protecting the wick, which of itself holds aconsiderable quantity of the liquid; third, in guarding against theslipping back of the wick in such lamps; fourth, in the in troduction insuch lamps of a device for preventing the overflow of the liquid at thejunction of the cap and neck of the lamp; and fifth, in guarding againstoverflow from excessive capillary action.

Figure 1, is a perspective view of the lamp; Fig. 2, a vertical middlesection; Fig. 3, a view of the wick tube; Fig. 4:, a vertical middlesection of the same; Fig. 5, a horizontal section of the safety chamberthrough the line 00 m of Fig. 4.

The accidents from these lamps arise chiefly from the five followingcauses: First, the spilling of the contents by upsetting the lamp whenthe cap happens to be loose, or removed, as in the act of filling thelamp; second, the passage of flame into the lamp between the cap andneck of the lamp, when the cement there becomes loose or detached, orwhen the lamps are imperfectly made at this point; leakage fromagitation may also occur in such case, and cover the outer surface ofthe lamp, and give rise to explosion, or crack the lamp if it be ofglass; third, the dropping of the wick back through the tube into thelamp from any cause, which leaves a package for the flame into the lamp;fourth, from the flooding or overflow of the fluid at the top of thewick, which happens whenever the fluid is drawn up, faster than it canbe consumed, from agitation or other causes; in this case the fluidspreads upon the lamp, ignites, and either cracks the lamp, or heats itso as to drive out either the cap, or force up a greater supply offluid, and from the alarm of the moment, frequently causes the lam to bethrown down, thus increasing the evil that otherwise might have beenavoided; fifth, flame is liable to pass into the lamp from the looseningof the wick tubes, or from imperfections in the top cap. e guard againstall such accidents in the following manner: Connected permanently withthe lower part of the cap (7)) is a metallic tube or casing as we termit closed at the bottom with wire gauze (h), and it will readily beseen, that should the lamp upset, with the upper cap (a,) loose ordetached, but a small portion of the fluid could run out, and thatslowly. The wire gauze intercepts all flame, and the tube and gauzetogether prevent spilling. The cap of this lamp is made so as to becemented to the outer and inner surface of the neck of the lamp, whichdiminishes the chance of leakage at that point. It is represented insection at (c, Fig. 2,) and although a well known device for otherpurposes, yet in this particular lamp has a two fold advantage, viz, itprevents leakage; and the inner ring of the cap, as seen at (1%,) servesas a support for the tube (g). The difference be tween this and thecommon cap is, that here the cap has two concentric rings between whichthe neck of the lamp is embraced while in the common cap there is butone ring. At (7') is a small opening in the tube (g), protected withwire gauze for purpose of allowing air to escape when the lamp is beingfilled.

The wick tube of the lamp is composed of two principal parts, an upperand lower part. The upper part (70,) is firmly fixed to the upper cap(a) and the lower part (m,) is fastened to this cap by a screw, as seenat The upper end of the lower part of the wick tube (1%,) passes througha circular plate (f, Figs. 4 and 5,) in which there are numerousperforations, and a wire gauze protection below; and from this platerises the screw thread (y), for fastening the lower portion of the wicktube (m,) to the cap. The screw may be omitted and the two parts unitedpermanently. The extremity of the wick tube projects a little above theplate (f,) and is provided with spring barbs, curving inwardly toprevent the wick from slipping back into the lamp. Between theperforated plate and the upper part of the cap, is a chamber (6), and itwill be readily understood, that any surplus of liquid drawn or carriedup by excessive capillary action or by agitation or otherwise will flowover at this point, and down through the wire gauze partition.

The lower portion of the wick tube (m), is provided with a chamber madeof perforated sheet metal, to contain the loose portion of the wick; andthis may be closed at the bottom or not by a cap, perforated or not atpleasure. It is to be understood that the spout of the can used forfilling the lamp is to be protected by wire gauze in a manner long knownforsuch purpose. In

relation to the device for preventing the falling back of the wick, weconsider this to be of the utmost importance in lamps for burningvolatile ingredients for guarding against the return of the wick in suchlamps.

lVe do not claim the use of perforated metal, or of wire gauze as ameans of protection in these lamps; but

We claim as our invention- 1. The combination of the safety wicktubeconstructed as described with the safety tube or casing around it.

2. In combination with the safety tube or casing, the perforated safetychamber with its tube barbed at the top to contain and hold the wick inplace.

3. Making the wick tube in two parts or divisions separable or not,substantially as herein-set forth, so as to form the safety chamber inwhich the barbed portion of the lower wick tube terminates.

E. N. HORSFORD. JAS. R. NICHOLS. Witnesses:

CHARLES R. MnToALr, CHARLES C. METoALr.

